Digital lighting technologies, i.e. illumination based on semiconductor light sources, such as light-emitting diodes (LEDs), offer a viable alternative to traditional fluorescent, HID, and incandescent lamps. Functional advantages and benefits of LEDs include high energy conversion and optical efficiency, durability, lower operating costs, and many others. Recent advances in LED technology have provided efficient and robust full-spectrum lighting sources that enable a variety of lighting effects in many applications. Some of the fixtures embodying these sources feature a lighting module, including one or more LEDs capable of producing different colors, e.g. red, green, and blue, as well as a processor for independently controlling the output of the LEDs in order to generate a variety of colors and color-changing lighting effects, for example, as discussed in detail in U.S. Pat. Nos. 6,016,038 and 6,211,626, incorporated herein by reference.
It is often desirable to illuminate an object to create a pleasing presentation of consumer products, ornamentation, sculptures, artwork, or other types of objects that can be found, for example, in museums, art galleries, retail environments, hotels, and in homes, among other places. Directional lighting effects are used in many applications in which a presentation object or scene, or a specific portion of the object or scene, is intentionally accentuated or emphasized with light.
For example, spotlights are typically used to create directional lighting effects on presentation objects. These spotlights are often permanently installed or are provided by mechanically movable lighting fixtures. These existing spotlight systems are limited and inflexible, making it difficult to create dynamic light effects or illuminate an object from multiple sides, particularly in a coordinated fashion. In many spotlight systems, numerous light sources must be installed separately and must be connected and commissioned in order to be controlled as a single system to provide directional lighting effects. For example, circular lighting fixtures in the shape of a ring are used as an accessory for a camera to illuminate a subject. These circular lighting fixtures, however, provide very limited range of lighting effects.
Thus, there is a need in the art to provide a lighting fixture with a plurality of individually-addressable LED-based light sources that can create dynamic lighting effects that illuminate a presentation object from multiple angles.